Rho-associated coiled-coil-containing protein kinase inhibitor Y-27632 promotes distraction osteogenesis healing by activating both osteoblasts and osteoclasts.

Distraction osteogenesis can induce substantial skeletal tissue regeneration; however, the treatment duration is long, making the procedure suboptimal for clinical care. Rho-associated coiled-coil-containing protein kinase inhibitors might promote bone generation in distraction osteogenesis and shorten treatment durations. However, the relationship between Rho-associated coiled-coil-containing protein kinase inhibitors and distraction osteogenesis levels has not been described. In this study, we focused on osteoblasts and osteoclasts, which are essential for bone remodeling and regeneration. Proliferation assay, boyden chamber, and wound healing assay were performed on MC3T3-E1 and RAW264 cells. Osteogenic differentiation assay was performed on MC3T3-E1 cells, and osteoclast differentiation assay was performed on RAW264 cells. Samples collected from distraction osteogenesis model mice were subjected to micro-computed tomography analysis and tissue staining. We found that Y-27632, a Rho-associated coiled-coil-containing protein kinase inhibitor, promoted cell motility and affected cell differentiation and bone differentiation in MC3T3-E1 preosteoblast cells. We also found that Y-27632 promoted cell motility and osteoclast differentiation in the osteoclast precursor RAW264 cells. In vivo experiments showed that the local administration of Y-27632 in a mouse distraction osteogenesis model promoted bone formation and increased the number of osteoblasts and osteoclasts in the distraction osteogenesis gap. These findings demonstrate that Y-27632 promotes bone formation in a mouse distraction osteogenesis model. Collectively, the study findings suggest that Y-27632 can be used as a therapeutic agent to promote distraction osteogenesis healing.